The Swanson Speed Square and the One-Number Method of determining the angular pitch of a roof were first developed in 1925 by a carpenter named Albert J. Swanson. As his fellow tradesmen began to appreciate the ingenuity of his idea, they wanted their own Speed Squares. Swanson began to hand-make the squares to fill requests for the tool. Demand for the work-saving tool continued to grow, and in 1930 the Swanson Speed Square was first sold in interstate commerce. By 1945, Swanson started Swanson Tool Company, Inc., to manufacture and sell the Swanson Speed Square through recognized channels of distribution. His son, Ronald C. Swanson, assumed control of the company in 1971 and added other quality tools to the line.
Today Swanson Tool Company continues to proudly manufacture and distribute the Swanson® Speed Square and other fine carpentry tools from its headquarters in Frankfort, Illinois. Under the direction of the Allemand Family, who purchased the company in 1989, the Swanson product line has been upgraded and expanded to meet the changing needs of loyal customers, contractors and do-it-yourself enthusiasts.